Pneumatic action for automatic musical instruments



S. A. SWANSON. PNEUMATIC ACTION FOR AUTOMAIICMUSICAL INSTRUMENTS. APPLICATION FILED mmsnwn. 1,314,163.

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5 a 7 V w W. H w m .Zi M" jel/ifbyor Z Ju/uwo r 3 UNITED STATES PATENT OFFICE.

SELVIYOR A. SWANSON, OF NORTH TONAWANDA, NEW YORK.

PNEUMATIC ACTION FOR AUTOMATIC MUSICAL INSTRUMENTS.

Specification of Letters Patent. Patented Aug. 26, 1919.

Application filed January 31, 1917. Serial No. 145,623.

Instruments, of which the-following is a specification.

My invention relates to improvements in pneumatic actions for automatic musical instruments, and the primary object of the invention is to provide an improved construction of the pneumatic action.

In automatic musical instruments, in order to obtain perfect action and proper timing of parts, the various operating parts must be accurately adjusted, and as the various mechanisms controlling Such. action are subject to wear, it is found necessary to occasionally replace one or more parts, and in present forms of construction this is found extremely diflicult, since it is necessary to remove the entire mechanism from the instrument.

It is the purpose of my invention to so construct the pneumatic action that the parts thereof are readily accessible from the front of the instrument without removing the entire mechanism, and to this end the valves and controlling devices are positioned that each one may be separately adjusted or removed and replaced, as may be required, without in any manner coming in contact with or displacing other parts of the mechanism. This is a very desirable feature in automatic player instruments, since it is now found necessary in most every instance to disassemble the parts in order to gain access to a single part requiring adjustment or repairs.

My invention consists in so arranging and positioning the action mechanism within the instrument that ready access may be had to: any individual part that may possibly require adjustment, repairs or replacement; such adjustment, repairs or replacement being made without in any manner affecting or changing the the action mechanism.

I have illustrated this arrangement in the drawings in which like numerals of reference refer to like parts, and in which,

Figure 1 is a fragmentary sectional front elevation of the action mechanism, showing the arrangement of the pneumatics on the Improvements in position of any. other part of valve chests, the position of the parts in reference to said pneumatics, and the position of the controlling devices for adjusting the collapsing and the expanding actions of the pneumatics.

Fig. 2 is a cross section through a portion of a musical instrument showing the position and arrangement of my improved action mechanism within the instrument.

The invention is shown as applied to that type of automatic player known as a piano player, but it is to be understood that it may be applied to an orchestrion or any other musical instrument. 7

In the particular representation of my invention herein disclosed, it is to be understood that the usual tracker bar is provided over which the perforated music sheet is adapted to travel, and as this is common in automatic musical instruments, I have not considered it necessary to illustrate the same except to show the tubes which connect the tracker bar with the action mechanism.

The pneumatic action mechanism is shown in connection with the hammer action mechanism of a piano and comprises two chests 3, 4, which are preferably arranged one above the other. These chests are in communication at opposite ends by means of ducts 5, and to the lower end of one of these ducts a tube 6 is secured which leads to the suction bellows of the instrument, as is common in the art.

7 designates the main chambers of the chests 3, 4, which chambers extend the full length of the chest. Each of these main chambers is connected to numerous L-shaped passages 8 through the medium of openings 9 and each of said openings is adapted to be closed by a valve 10 secured to a stem 11 extending through a removable bushing or cap 12 fitting into an opening in the front wall of the chest, which wall also serves as the front wall of the L-shaped chamber in which said valve is located. Said valve is guided in said bushing or cap and also in-a strap or guide 13 secured to the wall 14:, separating the L-shaped passage from the main chamber 7.

Each of the chests has a number of chambers 15 which are separated from the main chamber 7 by walls 16, and each of said walls has an opening 17 formed therein which is closed by a valve pouch 18. The chambers 15 have tubes 19 connected there with which lead to the tracker bar of the instrument, and in each of the walls 16 is a bleeder opening 20 which connects the chamber 16 with the main chamber 7 Secured to the movable wall of each pneumatic is an arm 22 through which extends an adjusting screw 25 having an adjusting nut 26 applied thereto which is adapted to bear against said arm. The rear end of each of said adjusting screws is pivotally secured to the end of one arm of a bell crank lever 27, the end of the other arm of said lever being adapted to actuate a wippen 28 pivotall'y secured to a support, as at 29, or otherwise. The wippens 28 are adapted to actuate the striking hammers 30 to bring them in contact with the strings 31 of the instrument. The bell crank levers 27 are pivotally secured to a transverse supporting bar 32 by means of which, the action mechanism may also be supported. Depend ing from the vvippens 28 are abstracts 33 which are adapted to be actuated by the manual keys 34 in. the usual manner, said keys and abstracts being disconnected so that the latter may move independent of the manual keys when the player is operated automatically. The relative arrangement of the wippens 28 and the actuating levers 2 is such that the wippens may be actuated through: the medium of the manual keys without in any manner affecting said levers. This, however, is common in instruments of this type. c

The pneumatics 15 of the chests 3 and 4; are arranged in staggered order, the arms 22 of the lower pneumatics extending upwardly" while those of the upper pneumatics extend downwardly between the arms of the lower pneumatics. The adjusting screws 25 passing through these arms are arranged so that access may be had to them fromthe front of the instrument without removing or disarranging any parts of the mechanism, it being simply necessary to insert the hand between the two chests 3 and 4t and manipulate theadjusting nut 26 of the desired adjusting screw, thus increasing or diminishing the stroke of the levers 27, and consequently the. stroke of the actuating hammers 30:

Iffor any reason access is desired to the valves 10, it is simply necessary to remove the bushings or caps 12 which are threaded or otherwise removably' fastened to the front walls of the chests, the openings closed by said bushings or caps-beingsomewhat larger than thevalves so that when thebushings or caps are removed, the valves with their stems can be easily withdrawn; Inorder to gain access to these parts it is simply necessary to remove the front' 35'of' the instrument, which is conveniently provided for in all instruments of thistype.

In: order to: control: the collapsing move ment of-thepneumatics, GEtCllAOfi the: cheats 3, 41 have lugs 36 secured thereto, the lugs of the upper chest being on the underside of the same and those on the lower chest being on the upper side of the same in line with the arms 26 of the pneumatics carried by said chests. Threaded through said lugs are regulating screws 37 which are provided with contact heads 38 at their inner ends against which the arms 26 of the pneumatics are adapted to strike, said heads being faced with felt or other soft material to render the mechanism noiseless. These regulating screws are adjustable in the lugs 36 in order to vary the position of the heads 38 with respect to the arms of said pneumatics. The heads 38 lie in a plane forward of the front 'faces of said chests and are conveniently accessible by removing the front wall 35 of the instrument.

It is apparent therefore that all parts requiring adjustment are readily accessible without in any manner disarranging or interfering with the action of any of the other parts; also without removing the action chests from the instrument, as is now found necessary.

The mechanism operates and is controlled inexactly the same manner as other action mechanisms now in use, it being controlled by the air entering tubes 19 through a tracker bar over which a perforated music sheet passes, the air entering the chest through said tubes acting against the secondary pneumatics or pouches 9 and forcing them toward the valves 10. This unseats the valves and causes the suction in the main chamber 7 to draw upon the pneumatics so that they collapse; the: extent of collapseof these pneumatics being regulated by the regulating screws, broadly termed controlling devices. These pneumaticsinturn actuate the bell crank levers 37,- the movements of which are controlled by thev adjusting screws 25, also broadly termed controlling devices, and these levers actuate: the wippens to the end that the hammers- 30 be brought into forcible contact with the strings 31.

It is of course understood that there is one striker pneumatic; one valve pouch, and one valve for each tone to be played, and that these are controlled individually by the in-rush of atmospheric air intocorresponding openings in the tracker bar, which inrush of air is controlled by the perforated music sheet passing over the tracker bar.-

When the opening or openings of the music sheet have passed over the: correspondlng openings in the tracker bar, the atmospheric air is shut off and the suction in the main chamber of the chests acts through the bleeder openings 20 and permits the return of the valve pouches 18 to normal position, which also causes the valves 10 to be closed:

It is apparent that my improved action chest may be associated with mechanism adapted to actuate musical devices or elements other than the strings 31, and that the novel features of my invention may be used in connection with pneumatics controlling, winding, or rewinding mechanism usually employed for controlling the movement of the perforated sheet over a tracker bar, also in connection with any mechanism capable of being controlled by pneumatics acting in a manner similar to those herein shown and described.

It is also to be understood that various changes in the combination and arrangement of parts: may be resorted to and that the action mechanism may be variously constructed, yet permit the retention of my improved mechanism for adjusting the movement of the parts and for moving certain parts of the mechanism without displacing, disarranging, or in any manner interfering with other parts of the mechanism.

Having thus I claim is,- v

In a player piano, a pair of action chests having main chambers, said chests being arranged the one above the other and having a duct establishing communication between the one of said chambers and the other at the ends thereof and provided with passages and chambers, the passages being arranged described my invention, What Copies of this patent may be obtained for five cents each, by addressing the for admitting atmospheric pressure thereinto to influence the movement of said pouch, a valve normally seated upon said opening and arranged to be actuated by said pouch whereby communication i established between said passage and main chamber, a plurality of pneumatics carried by each of said action chests and communicating with said passage, the pneumatics of one chest eing arranged in staggered relation with respect to those of the other chest, all of said pneumatics being located above the key board and in front of the strings of the piano, an arm carried by each of the pneumatics, a transversely arranged supporting bar, a bell-crank lever pivotally connected with said supporting bar, an adjustable screw connecting one of said bellcrank levers with said arm, said screw being arranged for varying the distance of one end of said lever from the pneumatic, a striking hammer, means associated with said hammer to be acted upon by said bell-crank lever, and an adjustable screw adapted for longitudinal adjustment to vary the collapsing movement of the pneumatics.

In testimony whereof I aflix my signature.

SELVIYOR A. SWANSON.

Commissioner of Patents,

Washington, D. 0." 

